结核分枝杆菌DNA指纹技术及其应用研究

目的　从分子流行病学角度探讨北京及其他地区结核分枝杆菌(结核菌)的分布特征。方法　构建以IS6110为基础的结核菌DNA指纹图谱，应用MINTS软件进行处理，并用χ2检验比较不同组别结核病人临床分离菌株成簇率的差别。结果　H37Rv、BCG两个标准菌株和62例结核病人临床分离菌株IS6110DNA指纹结果与国外同类报道一致；其中70%（44/62）的临床分离菌株IS6110DNA指纹相似值在1.00～0.65之间；分组统计结果显示，男性组与女性组成簇率之间差异有显著性（P<0.05），其他各组之间差异无显著性（P>0.05）。结论　DNA指纹技术对结核菌在株水平的鉴定具有特异、灵敏等优点，可应用于结核流行病学研究。研究表明，北京及其他地区结核菌临床分离菌株多数遗传关系较近，且在基因水平上相关程度较强；结核菌在男性人群中的传播频率可能较女性更高。

DNA fingerprinting technique of Mycobacterium tuberculosis and its usage

Objective　To explore the epidemical distribution characteristics of Mycobacterium tuberculosis isolates of Beijing and its surrounding areas by analyzing their IS6110-based DNA fingerprintings. Methods　DNA fingerprintings of H37Rv, BCG and 62 isolated strains from patients of TB were subjected to restriction fragment length polymorphism (RFLP), and then clustered by microbiology information numeral taxonomy system. The clustering values in different patients with tuberculosis were compared by χ2 test. Results　IS6110 DNA fingerprint patterns of H37Rv, BCG and isolates were consistent with those reported elsewhere. The similarity values of 70% isolates (44/62) were 1.00～0.65. There was a significant difference between female and male in the clustering (P<0.05). Conclusion　Major strains originated from patients in Beijing and its surrounding areas were closely related. Men were shown to be infected by related or identical strains more often than women.